Hinged and segmented pipe

ABSTRACT

A rigid pipe ( 1 ) is achieved according to the invention in that half-cylinder shaped elements ( 2 ) are joined/hinged ( 3 ) to each other and where to a such chains are connected together with their concave sides in a zipper-like motion. The two half-cylindrical chains are spooled ( 13 ) up individually on each side of a housing ( 12 ). This result in a particularly rigid pipe of varying length with a wide area of use.

TECHNICAL FIELD

The present invention relates to a rigid pipe comprised of hinged andsegmented semi-cylindrical pipe sections that are sequentially joinedtogether to form a rigid pipe having a long stroke-length that can beused in machines, tools, constructions or as an independent unit.

BACKGROUND ART

The prior art comprises solutions such as cylinders, telescopiccylinders, rack-and-pinion devices, threaded poles, manipulators,scissor-actuated lifts, coiled pipes, or combinations thereof.

From U.S. Pat. No. 6,283,203 is known a device for drilling oil wells.This device comprises two rack-and-pinion elements having an H-profilein a guide that among other things raises and lowers a pipe in adrilling tower.

From SE 459 267 is known an elongated cylindrical sleeve comprised oftwo flexible, semi-cylindrical bands that are wound on spools, andsequentially joined together to form the sleeve. This sleeve howeverdoes not form a rigid cylindrical pipe of sufficient structuralintegrity to be used in industrial settings.

DISCLOSURE OF THE INVENTION

The present invention provides a rigid pipe that can be formed ofdesired length. The pipe is comprised of two chains of semi-cylindricalpipe sections joined by hinges, that are sequentially locked together toform the rigid pipe. Because the two separate chains of pipe sectionsare articulated prior to being assembled, the chains may be stored onspools in a housing prior to assembly, thus achieving considerableeconomy of space, among other advantages that will be apparent to oneskilled in the art.

Several advantages of the invention in relation to the prior art are:

-   -   Longer stroke-length, more compact. Smaller dimensions when        assembled.    -   Simpler design, less expensive, faster to produce, less        expensive spare parts.    -   Adapted for the mounting of various tools at the end of the        pipe.    -   Simple drive unit that does not require large amounts of        hydraulic fluid.    -   Large capacity (power) and speed

The invention will be described in detail with reference to thefollowing figures, wherein,

FIG. 1 shows both a perspective view of the rigid pipe and housing, anda detailed view of one embodiment the rigid pipe having threads on itsoutside surface.

FIG. 2 shows two detailed views of the hinge and locking means

FIG. 3 shows cross sectional view of the pipe sections wound in ahousing

FIG. 4 detailed view of pipe sections being joined together in a guide,and a cross section of two joined pipe sections

A rigid pipe of varying length (1) is achieved according to theinvention in that half-cylinder shaped elements (2) are hinged (3) toeach other and in that the concave sides of two of such chains areconnected together in a zipper-like motion. The term “zipper-likemotion” is implicitly understood to mean that opposing half-cylindershaped elements are sequentially joined together to form a rigid pipe ofdesired length.

The two half-cylindrical chains are rolled up on the each side of thepipe.

In a zipper-like motion, the opposing half-cylindrical elements (2) arelocked (4) to each other with the object of preventing the pipe fromcoming apart/becoming deformed under a load. The term “zipper-likemotion” further implies that the locking means (4) from one cylindricalelement (2) is complimentary to the locking means (4) from the opposingcylindrical element (2) to which it is attached.

The pipe elements are rolled (13) together in a housing (12) comprisinga spool arrangement (5) and a guide (6) that leads the two halvestogether. In addition, the housing comprises a drive unit (7) thatmaneuvers the assembled pipe (1) out and in.

The drive unit (7) can function using a threaded pipe-,rack-and-pinion-, active spooling-, or friction principle. With thelast-mentioned type, the elements can have a smooth surface. The driveunit will thus function in a similar manner as for a coiled pipe. In thecase of a threaded pipe (8) and rack-and-pinion systems, the elementsmust have threads or teeth respectively. One can envision an activespool arrangement (5) that drives the pipe (1) out.

The purpose of the guide (6) is to lead the two halves together or apartfrom each other and to prevent rotation of the pipe.

The half-cylindrical elements (2) can be reinforced with internal crosswalls (10) and longitudinal ribs (11) to increase in the mechanicalstrength of the connected pipe (1).

1. A rigid pipe of variable length (1), comprising a first elongated,articulated pipe-half joined to an opposing second elongated,articulated pipe-half, said elongated pipe-halves being individuallywound on spools (5) in a housing (12) and are progressively connected toeach other to form a pipe (1) of desired length, characterized in thateach elongated, articulated pipe-half is formed as a chain of rigid,semi-cylindrical pipe sections (2) joined together in series at theiropposing ends by hinges (3), and further characterized in that eachrigid pipe section (2) from the first elongated pipe-half comprises alocking means (4) that is complimentary to a locking means (4) on theopposing rigid pipe section (2) from the second elongated pipe-half,such that the complimentary locking means lock the flexible pipe-halvestogether with their concave side directed towards each other forming anelongated rigid pipe of desired length.
 2. A rigid pipe according toclaim 1, characterized in that each rigid pipe section (2) comprisesinternal cross-walls (10) and/or longitudinal ribs (11) for increasingthe rigidity of the pipe.
 3. A rigid pipe according to claim 2,characterized in that the rigid pipe sections (2) are brought intoopposing alignment with each other by the help of a guide member (6),and that each rigid pipe section (2) has a groove (9) on its convexouter surface that engages a portion of guide member (6) to preventrotation of the pipe sections.
 4. A rigid pipe according to claim 3,characterized in that the rigid pipe sections are brought progressivelytogether by the help of a drive unit (7) that actively drives the rigidpipe sections out of housing (12).
 5. A rigid pipe according to claim 4,characterized in that the convex outer surface of the rigid pipesections (2) comprises threads (6) that engage corresponding threads ofdrive unit (7).
 6. A rigid pipe according to claim 4, characterized inthat the convex outer surface of the rigid pipe sections (2) comprisesteeth that engage corresponding teeth of drive unit (7).
 7. A rigid pipeaccording to claim 4, characterized in that the convex outer surface ofthe rigid pipe sections (2) is smooth, and engages corresponding smoothrollers of drive unit (7) by friction.
 8. A method for forming a rigidpipe (1) of variable length from two elongated, articulated pipe-halves,characterized by comprising the steps of: forming each of the twoelongated, articulated pipe-halves by connecting a plurality of rigid,semi-cylindrical pipe sections (2) together in a chain by hingedconnections (3) between opposing ends of the rigid sections (2);arranging each chain of rigid pipe sections (2) on a separate spool (5)in a housing (12) of a connection device, the connection device furthercomprising a guide member (6) and a drive unit (7); bringing theelongated pipe-halves together in a progressive manner such that theconcave sides of each pipe section is successively arranged facing theconcave side of an opposing pipe section; equipping each rigid pipesection (2) with a locking means (4) that is complimentary to a lockingmeans (4) on its opposing pipe section; Pressing the opposing pipesections together such that they lock together; and Continuously feedingpipe sections from the connection device until a rigid pipe of desiredlength is obtained.
 9. The method according to claim 8, characterized inthe outer convex surface of the rigid pipe sections (2) is smooth, andengages a plurality of smooth rollers of drive unit 7 by friction. 10.The method according to claim 8, characterized in the outer convexsurface of the rigid pipe sections (2) has threads (6) or teeth thatengages corresponding threads or teeth on a plurality of rollers ofdrive unit (7).